Aerial advertising displays include skywriting, signs and logos on the sides of dirigibles, parachutists with indices on their canopies or having banners suspended from them during flight, and banners towed behind fixed-wing aeroplanes or suspended from slower moving aircraft such as helicopters, dirigibles and balloons. Aerial advertising displays have the advantage of being able to be seen by many thousands of people at gatherings such as outdoor concerts, sporting events, carnivals, shows, celebrations and by other members of the public outside at the beach, park, in the city or just walking around the streets.
Banners towed behind aeroplanes have the disadvantage of needing to be long and thin to minimise the drag to the aeroplane such as described in British Patent No. GB 463196A. Accordingly, most aeroplane banners are single line messages in plain font with little or no scope to display flags, logos, devices or signs. Further the high air speed of aeroplanes means that the message being displayed is not in the field of view of most spectators for very much time. Furthermore fixed-wing aeroplanes generally have restricted corridors in which they can fly over cities further limiting the time in which the advertising display is in the field of view of spectators.
Slower-moving aircraft such as helicopters, dirigibles and balloons often are allowed greater access to airspace over cities. The aircraft are more manoeuvrable and often are able to be better positioned for viewing by spectators whilst the lower airspeed allows for larger banners and flags to be towed below and behind the aircraft. A ballast is often also required to be attached from the flag bearing line suspended from the aircraft to keep the line taut and the flag or banner unfurled and correctly displayed during flight. The lower airspeed of the aircraft even to the point of hovering provides further advantages in that the aircraft and hence the advertising display stays in the field of view of spectators for greater lengths of time.
However a main disadvantage of ballasted flags and banners towed or suspended from aircraft is the danger presented to the public and the likelihood of property damage if the ballast or entire advertising display falls to earth after being released from the aircraft such as in an emergency or by accident. The Civil Aviation Safety Authority responsible for civil air safety in Australia generally does not permit helicopters and airships to fly over land with ballasted advertising displays suspended from the aircraft due to the potential danger to property or the public should the ballasted display become disconnected from the aircraft and fall. Approval for ballasted aircraft held advertising displays is generally only given for flights over water, which severely restricts the benefits and advantages provided by aircraft advertising displays for the viewing public.
Accordingly then there exists a requirement for further developments and improvements in ballasted aerial advertising displays or at least the provision of an alternative to existing aerial advertising display systems. In particular there exists a requirement for an emergency drop system for a ballasted advertising display suspended from an aircraft to allow the aircraft to be flown over land, property, buildings and the public without any significant risk of harm to the public or damage to property if the ballasted display separates from the aircraft during flight.